

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

/**
 * @date          2011-07-14
 * @class         UdpGetClientMacAddr
 * @extends       Object
 * @description   获取客户端mac地址工具类
 */
public class UdpGetClientMacAddr
{
    private String sRemoteAddr;
    private int iRemotePort = 137;
    private byte[] buffer = new byte[1024];
    private DatagramSocket ds = null;

    public UdpGetClientMacAddr(String strAddr) throws Exception
    {
        sRemoteAddr = strAddr;
        ds = new DatagramSocket();
        ds.setSoTimeout(5000);
    }

    protected final DatagramPacket send(final byte[] bytes) throws IOException
    {
        DatagramPacket dp = new DatagramPacket(bytes, bytes.length, InetAddress.getByName(sRemoteAddr), iRemotePort);
        ds.send(dp);
        return dp;
    }

    protected final DatagramPacket receive() throws Exception
    {
        DatagramPacket dp = new DatagramPacket(buffer, buffer.length);
        ds.receive(dp);
        return dp;
    }

    protected byte[] GetQueryCmd() throws Exception
    {
        byte[] t_ns = new byte[50];
        t_ns[0] = 0x00;
        t_ns[1] = 0x00;
        t_ns[2] = 0x00;
        t_ns[3] = 0x10;
        t_ns[4] = 0x00;
        t_ns[5] = 0x01;
        t_ns[6] = 0x00;
        t_ns[7] = 0x00;
        t_ns[8] = 0x00;
        t_ns[9] = 0x00;
        t_ns[10] = 0x00;
        t_ns[11] = 0x00;
        t_ns[12] = 0x20;
        t_ns[13] = 0x43;
        t_ns[14] = 0x4B;

        for (int i = 15; i < 45; i++)
        {
            t_ns[i] = 0x41;
        }

        t_ns[45] = 0x00;
        t_ns[46] = 0x00;
        t_ns[47] = 0x21;
        t_ns[48] = 0x00;
        t_ns[49] = 0x01;
        return t_ns;
    }

    protected final String GetMacAddr(byte[] brevdata) throws Exception
    {

        int i = brevdata[56] * 18 + 56;
        String sAddr = "";
        StringBuffer sb = new StringBuffer(17);

        for (int j = 1; j < 7; j++)
        {
            sAddr = Integer.toHexString(0xFF & brevdata[i + j]);
            if (sAddr.length() < 2)
            {
                sb.append(0);
            }
            sb.append(sAddr.toUpperCase());
            if (j < 6)
                sb.append('-');
        }
        return sb.toString();
    }

    public final void close()
    {
        try
        {
            if(ds != null)
            {
                ds.close();
            }
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }
    }

    public final String GetRemoteMacAddr() throws Exception
    {
        byte[] bqcmd = GetQueryCmd();
        send(bqcmd);
        DatagramPacket dp = receive();
        String smac = GetMacAddr(dp.getData());
        close();

        return smac;
    }
    
    public static void main(String[] args)
    {
        try
        {
            UdpGetClientMacAddr mac = new UdpGetClientMacAddr("127.0.0.1");
            String ma = mac.GetRemoteMacAddr();
            System.out.println(ma);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
}
